Method for preparing a catalyst and catalysts prepared accordingly

ABSTRACT

The present invention relates to a process for preparing a catalyst by activating a catalytic composition which comprises 
     a) at least one metal of group IB or IIB or a compound thereof, 
     b) where appropriate a carrier 
     which comprises treating the composition with an alkyne of the general formula I 
     
       
         R 1 —C≡C—R 2   (I) 
       
     
     in which 
     R 1  is alkyl, cycloalkyl, aryl, hydroxyalkyl, haloalkyl, alkoxy or alkoxyalkyl, 
     R 2  is a hydrogen atom, alkyl, cycloalkyl or aryl, and a carbonyl compound of the general formula II                    
     in which 
     R 3  and R 4  are, independently of one another, a hydrogen atom, alkyl, haloalkyl, cycloalkyl or aryl, 
     to catalysts obtainable by this process, and to alkynylations and aminoalkylations employing these catalysts.

This is the National Phase Application of PCT/EP98/07785, filed Dec. 01,1998.

The present invention relates to a process for preparing a catalyst byactivating a catalytic composition which comprises at least one compoundof a metal of group IB or IIB of the Periodic Table, where appropriatebismuth or a compound thereof, and where appropriate a carrier, and tothe catalysts obtainable by this process. The invention further relatesto a process for preparing alkynols and to a process for preparingaminoalkynes using these catalysts.

The preparation of alkynols by addition of a carbonyl compound onto analkyne and, in particular, onto acetylene with retention of the triplebond, and the preparation of aminoalkynes by reacting an alkyne with acarbonyl compound and an amine in a Mannich-type condensation have beenknown for a long time and used industrially. Both reactions can becatalyzed homogeneously or heterogeneously, generally employing heavymetal acetylides and, in particular, catalysts based on copper(I)acetylide.

U.S. Pat. No. 3,496,232 describes the preparation of N-alkyl-substitutedaminoalkynes in a homogeneously or heterogeneously catalyzed Mannichreaction, the catalysts employed being salts of metals of group IB orIIB, such as, for example, the chlorides, acetates, formates andacetylides and, specifically, copper acetylide. These can, in the caseof the heterogeneously catalyzed process variant, be employed on aninert carrier. The copper acetylide catalyst is prepared in this casebefore the actual Mannich reaction by reacting copper(II) chloride withparaformaldehyde and acetylene in an autoclave.

DE-A-23 14 693 describes a process for preparing butynediol by reactingacetylene and formaldehyde, employing a supported heavy metal acetylidecatalyst which is obtained by impregnating a carrier with a heavy metalsalt solution and subsequently treating with gaseous acetylene.

DE-A-24 21 407 likewise describes a process for preparing butynediol,employing supported copper acetylide catalysts.

DE-A-26 02 418 describes a process for preparing butynediol, employing asupported catalyst which is obtained by reacting a copper(II) compoundwith acetylene and formaldehyde in aqueous solution at a pH below 5.5.

U.S. Pat. No. 3,650,985 describes the prepartion of unsupported copperacetylide catalysts of the general formula(CuC₂)_(w)(CH₂O)_(x)(C₂H₂)_(y)(H₂O)_(z) with 1≦w, x, y<100, preferablyw=4, x=0.24 to 4, y=0.24 to 4 and z=0.67 to 2.8. These catalysts mayadditionally contain a bismuth compound and can be prepared byformaldehyde and acetylene acting simultaneously on the particulate,water-insoluble copper compound, preferably basic copper carbonate, suchas, for example, synthetically prepared malachite. They are used asaqueous catalyst suspension for the ethynylation of acetylenicallyunsaturated hydrocarbons. Similar malachite catalysts are described inU.S. Pat. No. 3,560,576.

U.S. Pat. No. 4,110,249 describes a process for preparingbismuth-modified spheroidal malachites and their reaction with acetyleneand formaldehyde to give unsupported ethynylation catalysts. U.S. Pat.No. 4,127,734 describes a process for preparing 1,4-butynediol byreacting acetylene and formaldehyde in the presence of these catalysts.

U.S. Pat. No. 4,536,491 describes agglomerates of spheroidal malachiteswhich comprise bismuth and silica. These malachites can be convertedinto copper acetylide complexes by reacting in the form of an aqueoussuspension with acetylene and formaldehyde. U.S. Pat. No. 4,584,418describes a process for preparing 1,4-butynediol by reacting acetylenewith formaldehyde in the presence of these catalysts.

U.S. Pat. No. 4,119,790 describes a continuous, multistage low-pressureethynylation process for preparing 1,4-butynediol, employing anethynylation catalyst based on a water-insoluble copper acetylidecomplex. This ethynylation catalyst is prepared by reacting a precursorwhich comprises between 20 and 35% by weight of copper and 0 to 3% byweight of bismuth on a magnesium silicate carrier with formaldehyde inthe presence of acetylene.

EP-A-0 080 794 describes a heterogeneously catalyzed process forpreparing N,N-disubstituted propynylamines, the catalysts employed beingcopper acetylides on a magnesium silicate carrier doped with bismuthoxide. These are conventional ethynylation catalysts which must beactivated before they are used with acetylene and formaldehyde.

The disadvantage of the catalysts described above is that they areprepared by activating a catalytic composition using acetylene.Operations with acetylene, which is a thermally unstable gas whicheasily explodes even under atmospheric pressure, are industriallycomplicated because considerable safety measures are necessary in thedesign of the reactors. This particularly applies to operations withliquefied acetylene and/or manipulation thereof under high pressures.The heavy metal catalysts obtained on activation of the catalyticcomposition with acetylene are also generally prone to explosivedecomposition and can therefore be manipulated only with difficulty.Processes in which catalysts of these types are employed are thereforeat a commercial disadvantage. This particularly applies when acetyleneis employed only in the preparation or activation of the catalyst, whilethe subsequent ethynylation or aminoalkylation reaction takes place withuse of a different alkyne.

It is an object of the present invention to provide a process forpreparing a catalyst by activating a catalytic composition allowing theuse of acetylene to be dispensed with.

We have found that this object is achieved by a process in which acatalytic composition which comprises at least one metal of group IB orIIB of a compound thereof, where appropriate bismuth or a compoundthereof, and where appropriate a carrier, is activated with an alkynedifferent from acetylene and with a carbonyl compound.

It has also been found, surprisingly, that the use of acetylene inactivating the catalytic composition can generally also be dispensedwith if the following alkynylation or aminoalkylation reaction iscarried out in the presence of acetylene, because the alkyne employedfor the activation can generally be different from the alkyne employedfor the following reaction.

The invention therefore relates to a process for preparing a catalyst byactivating a catalytic composition which comprises

a) at least one metal of group IB or IIB or a compound thereof,

b) where appropriate a carrier

which comprises treating the composition with an alkyne of the generalformula I

R₁—C≡C—R²  (I)

in which

R¹ is alkyl, cycloalkyl, aryl, hydroxyalkyl, haloalkyl, alkoxy oralkoxyalkyl,

R² is a hydrogen atom, alkyl, cycloalkyl or aryl, and a carbonylcompound of the general formula II

in which

R³ and R⁴ are, independently of one another, a hydrogen atom, alkyl,haloalkyl, cycloalkyl or aryl.

For the purpose of the present invention, halogen is fluorine, chlorine,bromine and iodine and, in particular, chlorine and bromine.

The term “alkyl” comprises straight-chain and branched alkyl groups.These are preferably straight-chain or branched C₁-C₁₂-alkyl and, inparticular, C₁-C₆-alkyl groups. Examples of alkyl groups are, inparticular, methyl, ethyl, propyl, 1-methylethyl, n-butyl,1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, n-pentyl,1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,2-dimethylpropyl,1,1-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl,1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl,1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl,1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethylbutyl,2-ethylbutyl, 1-ethyl-2-methylpropyl, n-heptyl, 1-methylhexyl,1-ethylpentyl, 2-ethylpentyl, 1-propylbutyl, octyl, decyl and dodecyl.

Haloalkyl is an alkyl group as defined above which is halogenated withone or more halogen atoms, in particular chlorine and bromine, partiallyor completely, preferably with one to three halogen atoms.

The above statements about the alkyl group and haloalkyl group apply ina corresponding manner to the alkyl group in alkoxy, alkoxyalkyl andhydroxyalkyl radicals.

Cycloalkyl is preferably C₃-C₈-cycloalkyl such as cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl, orcyclopentylmethyl, cyclopentylethyl and cyclohexylmethyl andcyclohexylethyl.

Aryl is preferably phenyl or naphthyl.

The catalytic composition preferably used in the process according tothe invention comprises copper or a copper compound as component a).Suitable copper compounds a) are selected, for example, from copperhalides such as copper(I) chloride, copper(II) chloride, copper(I)bromide and copper(II) bromide, copper(I) sulfate, copper(II) sulfate,copper(II) hydroxide, copper (I) oxide, copper(II) oxide, copperphosphates, copper silicates, basic copper carbonates etc., and mixturesthereof. Preferred copper compounds a) are copper(II) oxide and basiccopper carbonates such as natural and, particularly preferably syntheticmalachites.

Suitable bismuth compounds are selected, for example from bismuth oxideBi₂O₃, bismuth subcarbonate (BiO)₂CO₃, bismuth nitrate Bi(NO₃)₃ andbismuth subnitrate BiO(NO₃). Bismuth oxide is preferably employed ascomponent b).

The catalytic compositions employed for the activation in the processaccording to the invention may, where appropriate, comprise a carrier c)which is selected, in particular, from alumina, aluminosilicates,zirconium oxide, titanium dioxide and, preferably, silica.

The catalytic composition employed for the activation preferablycomprises 10 to 20% by weight of copper(II) oxide, 1 to 5% by weight ofbismuth oxide and 75 to 89% by weight of silica as carrier.

Supported catalytic compositions suitable for the activation are knownin the art and are described, for example, in U.S. Pat. No. 3,650,985,DE-A-26 02 418 and U.S. Pat. No. 4,119,790. The disclosure of thesepublications is incorporated herein by reference, although theactivation of the supported catalytic compositions described thereintakes place without use of acetylene in the process according to theinvention.

In a preferred embodiment of the present invention, an unsupportedcatalytic composition which comprises a Bi-doped malachite is employedfor the activation. Catalytic compositions of this type are described,for example in U.S. Pat. No. 4,110,249, DE-A-25 08 084 and U.S. Pat. No.4,536,491. The disclosure of these publications is likewise incorporatedherein by reference, although the activation of the unsupportedcatalytic compositions described therein once again takes place withoutuse of acetylene in the process according to the invention.

For the activation, the supported or unsupported catalytic compositionsdescribed above are treated with an alkyne of the general formula I anda carbonyl compound of the general formula II. The temperature duringthis is generally in a range from about 0 to 150° C., preferably about20 to 100° C. The pH of the reaction medium employed for treating thecatalytic compositions is generally in the acid or neutral range suchas, for example, at pH values from about 4.0 to 7.0, preferably in theslightly acidic range such as, for example, at pH values from about 5.5to 6.9. The pH can be adjusted by employing conventional bases such asalkali metal hydroxides, e.g. NaOH and KOH, alkali metal carbonates,e.g. Na₂CO₃ and K₂CO₃, and alkali metal bicarbonates, e.g. NaHCO₃ andKHCO₃. The catalytic composition is preferably activated as suspensionin water. However, it is also possible to employ mixtures of water andat least one completely water-miscible organic solvent which is inerttoward the reactants. Examples of suitable solvents are saturated cyclicethers, such as tetrahydrofuran and dioxane.

The pressure during the activation of the catalytic compositions isgenerally lower than in processes known in the art in which acetylene isemployed for the activation. The pressure in the process according tothe invention is generally up to about 3 bar, preferably up to about 2bar. In a particularly preferred embodiment, the activation of thecatalytic compositions takes place under atmospheric pressure.

If the alkyne of the general formula I employed is an alkyne which isgaseous under the reaction conditions, such as, for example, propyne orbutyne, the activation can, if required, be carried out under autogenouspressure while maintaining the pressure conditions described above. In apossible reaction procedure, the carbonyl compound of the generalformula II can then be introduced together with the unsupported orsupported catalytic composition and, where appropriate, with a solventinto a reactor equipped with a mixing apparatus. Suitable reactors areknown to the skilled worker. They include the reaction vessels describedin Ullmanns Enzyklopadie der technischen Chemie, 3rd edition, volume 1,page 117 ff. and page 769 ff. (1951) for reactions under pressure.Addition of the gaseous alkyne preferably takes place below the level ofthe liquid activation mixture introduced, e.g. with an immersion pipe ora coiled pipe having orifices in or opposite to the direction of flow ofthe reaction mixture. The rate of addition is limited by theabovementioned pressure ranges to be maintained.

If the alkyne of the general formula I employed is liquid or solid underthe reaction conditions, the activation can generally take place underatmospheric pressure in a reactor customary for this purpose and havinga mixing apparatus, e.g. in a stirred reactor. The activation can thentake place, for example, in a batch procedure, in which case thecarbonyl compound is preferably introduced into the reactor with asuspension of the unsupported or supported catalytic composition inwater and, where appropriate, a solvent, and the alkyne is fed,undiluted or as solution, into the reactor as it is consumed.

In a preferred embodiment of the process according to the invention, thecatalytic compositions are activated by employed alkynes of the formulaI in which the radical R¹ is alkyl or hydroxyalkyl. The radical R² ispreferably a hydrogen atom or alkyl. Examples thereof include propyne,1-butyne, 1-pentyne, 1-hexyne, 1-heptyne, 1-octyne, propynol,3-butyn-1-ol, 3-butyn-2-ol, 2-methyl-3-butyn-2-ol, 4-pentyn-1-ol,4-pentyn-2-ol, 4-pentyn-3-ol, 2-methyl-4-pentyn-2-ol,3-methyl-4-pentyn-2-ol, 3-methyl-4-pentyn-3-ol etc. Those preferablyemployed are 3-butyn-2-ol, 2-methyl-3-butyn-2-ol and 1-hexyne.

In a preferred embodiment of the process according to the invention, thecatalytic compositions are activated by employing carbonyl compounds ofthe general formula II in which R³ and R⁴ are, independently of oneanother a hydrogen atom or alkyl. Examples thereof include acetaldehyde,propionaldehyde, n-butyraldehyde, n-valeraldehyde etc. Formaldehyde or acondensate thereof, e.g. paraformaldehyde, is particularly preferablyemployed.

The process according to the invention is suitable not only forpreparing a catalyst by activation of a catalytic composition but also,advantageously, for reactivating a previously used, deactivatedcatalyst.

The invention further relates to the catalysts which are obtainable bythe process described above. It is possible in the preparation of thesecatalysts by the process according to the invention to dispense withactivation of the catalytic compositions with acetylene. This isparticularly advantageous when the resulting catalyst is to be employedin a process in which acetylene is likewise not used as reactant. It isthus generally possible to make such processes more economic using thecatalysts according to the invention because it is possible to dispensewith the safety measures needed for operations with acetylene. This isparticularly true when no gaseous alkynes are employed for activatingthe catalytic compositions, so that this can be carried out underatmospheric pressure. In contrast to the copper acetylides employed todate as catalysts, the catalysts according to the invention aregenerally not prone to explosive decomposition either, and can thus bemanipulated without hazard. The activity of these catalysts is generallyat least comparable to that of catalysts activated with acetylene.Particularly for the alkynylation of alkynes or hydroxyalkynes withterminal triple bonds the catalysts according to the invention generallyshow an activity which is as good as or better than correspondingcatalysts activated with acetylene. This also applies specifically toethynylation reactions using acetylene. Even if, as in this case,acetylene is employed for the catalyzed reaction, it is advantageous toemploy an alkyne different from acetylene for activating the catalyst.As described above, the catalysts according to the invention aregenerally not prone to explosive decompositions and can thus bemanipulated and stored more easily. The safety precautions necessary foroperations with acetylene are thus dispensed with at least for theactivation of the catalytic compositions.

The invention further relates to a process for preparing alkynols of thegeneral formula III

in which

R⁵is a hydrogen atom, alkyl, haloalkyl, cycloalkyl, aryl, alkoxy,alkoxyalkyl or a —C(R⁶R⁷)OH substituent,

R⁶ and R⁷ are, independently of one another, a hydrogen atom, alkyl,haloalkyl, cycloalkyl or aryl,

by reacting a mixture of an alkyne of the general formula IV

R⁵—C≡C—H  (IV)

in which

R⁵ has the meanings stated above, and a carbonyl compound of the generalformula V

in which

R⁶ and R⁷ have the meanings stated above,

wherein the reaction takes place in the presence of a catalyst accordingto the invention.

In a preferred embodiment of the process according to the invention, thecompounds prepared are those in which the radical R⁵ is a hydrogen atom,alkyl or a —C(R⁶R⁷)OH substituent. The radicals R⁶ and R⁷ arepreferably, independently of one another, a hydrogen atom or alkyl. Theradicals R⁶ and R⁷ are, in particular, both hydrogen.

The alkyne of the formula IV employed to prepared compounds of theformula III in which R⁵ is hydrogen is acetylene. The ratio of the molarquantities of acetylene and carbonyl compound of the formula V is thenabout 1:0.5 to about 1:1, so that essentially monoadducts result.

The alkyne of the formula IV employed to prepare compounds of theformula III in which R⁵ is a —C(R⁶R⁷)OH substituent is likewiseacetylene. The ratio of the molar quantities of acetylene and carbonylcompound of the formula V is then about 1:2 to 1:4, so that essentiallybisadducts result.

The alkynol of the formula III is preferably propynol, 2-butyn-1-ol,2-butyne-1,4-diol, 3-butyn-2-ol, 3-hexyne-2,5-diol, 3-pentyn-2-ol etc.

The invention further relates to a process for preparing aminoalkynes ofthe general formula VI

in which

R⁵, R⁶ and R⁷ have the meanings stated above,

R⁸ and R⁹ are, independently of one another, a hydrogen atom, alkyl,haloalkyl, cycloalkyl, aryl or hydroxyalkyl, or

R₈ and R⁹ form, together with the nitrogen atom to which they arebonded, a 5- or 6-membered heterocyclic ring;

by reacting a mixture of an alkyne of the general formula IV

R⁵—C≡C—H  (IV)

in which

R⁵ has the meanings stated above, a carbonyl compound of the generalformula V

in which

R⁶ and R⁷ have the meanings stated above, and an amine of the generalformula VII

in which

R⁸ and R⁹ have the meanings stated above,

wherein the reaction takes place in the presence of a catalyst accordingto the invention.

The radicals R⁸ and R⁹ can form, together with the nitrogen atom towhich they are bonded, a heterocyclic ring. Examples thereof aresuccinimido and phthalimido groups or an unsaturated or saturated, 5- or6-membered heterocyclic ring which optionally contains anotherheteroatom selected from S and N, preferably N. Examples thereof whichmay be mentioned are: piperidinyl, piperazinyl and tetrahydropyrimidinylgroups.

In a preferred embodiment of the process according to the invention thecompounds prepared are those in which the radical R⁵ is a hydrogen atom,alkyl or a —C(R⁶R⁷)OH substituent. R⁶ and R⁷ are preferably,independently of one another, a hydrogen atom or alkyl. The radicals R⁶and R⁷ are, in particular, both hydrogen. It is further preferred forthe radicals R⁸ and R⁹ to be, independently of one another, a hydrogenatom, alkyl or hydroxyalkyl. Suitable amines of the formula VII arethen, for example, dimethylamine, diethylamine, di-n-propylamine,diisopropylamine, di-n-butylamine, diethanolamine, dipropanolamine etc.

The alkyne of the formula IV employed to prepare compounds of theformula VI in which R⁵ is hydrogen is acetylene. The ratio of the molarquantities of acetylene and carbonyl compound of the formula V and amineof the formula VII is then about 1:0.5:0.5 to about 1:1:1, so thatessentially monoadducts result.

The alkyne of the formula IV employed to prepare compounds of theformula VI in which R⁵ is a —C(R⁶R⁷)OH substituent is likewiseacetylene. The ratio of the molar quantities of acetylene and carbonylcompound of the formula V and amine of the formula VII is then about1:2:2 to about 1:4:4, so that essentially bisadducts result.

The aminoalkyne of the formula VI is preferablyN,N-dimethylaminopropyne, N,N-diethylaminopropyne,N,N-dihydroxyethylaminopropyne, N,N-dimethylamino-2-butyne,N,N-diethylamino-2-butyne, N,N-dihydroxyethylamino-2-butyne,5-(N,N-dimethylamino)-3-pentyn2-ol and, in particular,5-(N,N-diethylamino)-3-pentyn-2-ol.

The alkynes of the formula I employed to prepare the catalysts accordingto the invention can in one embodiment correspond to the alkynes of thegeneral formula IV employed in the catalyzed alkynylation oraminoalkylation reaction. In this case, the catalysts can generally beprepared immediately before the alkynylation or aminoalkylation, itbeing possible to dispense with isolation and, where appropriate,purification of the catalyst. It is preferred for the preparation of thecatalyst and the subsequent reaction carried out therewith to take placein one reactor in a one-pot reaction.

In a further embodiment, however, the alkyne of the formula I employedto prepare the catalysts according to the invention can also differ fromthe alkynes of the formula IV employed in the catalyzed alkynylation oraminoalkylation reaction. This is, as described above, particularlyimportant when acetylene is employed as alkyne for the alkynylation oraminoalkylation. In this case, an alkyne different from acetylene can beemployed to prepare the catalyst, and the catalyst can, if desired, beprepared in a separate reactor. The resulting catalyst can be isolatedand purified by conventional processes, e.g. by washing with water.

The invention further relates to the use of the catalysts according tothe invention in alkynylation reactions and for preparing aminoalkynesby reacting an alkyne with a carbonyl compound and an amine.

The invention is illustrated in detail by the following, non-limitingexamples.

EXAMPLES

1) Activation of an Unsupported Catalytic Composition Based on Malachite

A catalytic composition with a Bi content of 4% is prepared as describedin DE-A-25 08 084.

377.5 g of formaldehyde (49% strength in water) are introduced undernitrogen into a 500 ml glass reactor with baffles and disk agitator,reflux condenser, temperature measurement, pH-electrode and feed foraqueous NaHCO₃ solution through an immersion tube, and heated to 70° C.and adjusted to pH 6.5 with NaHCO₃ solution (the temperature fallsslightly during this). Heating is continued until the temperature in thereactor reaches 75° C., and then 9.7 g of malachite catalyst aresuspended in 50 g of water and transferred into the reactor. Then 70.1 gof 3-butyn-2-ol (55% strength in water) are metered in continuously byan HPLC pump with stirring over a period of 4 h, during which thecatalyst becomes dark in color over the course of some hours. If the pHfalls below 6 during the activation reaction, 2% strength aqueous NaHCO₃solution is added to compensate (total of 372 ml). The activation iscompleted after 8 h by slowly cooling to 25° C.

The catalyst is then removed by centrifugation and washed twice withwater.

2) Activation of a Supported Catalytic Composition Based on Copper Oxide

The catalytic composition in the form of pellets is prepared asdescribed in DE-A-26 02 418.

377.5 g of formaldehyde (49% strength in water) are introduced undernitrogen into a 500 ml glass reactor with baffles and disk agitator,reflux condenser, temperature measurement, pH-electrode and feed foraqueous NaHCO₃ solution through an immersion tube, and heated to 70° C.and adjusted to pH 6.5 with NaHCO₃ solution (the temperature fallsslightly during this). Heating is continued until the temperature in thereactor reaches 75° C. (after about 15 minutes), and then 30 g ofsupported copper catalyst (pellets, about 15% CuO, 80% SiO₂ and 4% Bi₂ 0₃, diameter about 3 mm, length about 6 to 8 mm) are suspended in 50 g ofwater and transferred into the reactor. Then 70.1 g of 3-butyn-2-ol (55%strength in water) are metered in continuously by an HPLC pump withstirring over a period of 2.5 h. If the pH falls below 6 during theactivation reaction, 2% strength aqueous NaHCO₃ solution is added tocompensate (total of 100 ml). The activation is completed after 20 h byslowly cooling to 25° C. The catalyst is then filtered off and washedtwice with water.

3) Activation of an unsupported catalytic composition based onmalachite:

The procedure is analogous to the method of Example 1) but, in place ofthe 3-butyn-2-ol, 56.5 g of propargyl alcohol (55% strength in water) ismetered in by an HPLC pump. A total of 350 ml of NaHCO₃ solution isadded to adjust the pH.

4) Synthesis of diethylaminopentynol Using the Catalyst from Example 1

70.1 g (0.55 mol) of 3-butyn-2-ol (55% strength solution in water), 30.3g of paraformaldehyde (1 mol) and 10 g of the activated malachitecatalyst from Example 1 are introduced into a 250 ml stirred apparatus.After heating to 80° C., 73.1 g (1 mol) of diethylamine are addeddropwise with stirring over the course of 1 h. The reaction mixture isthen stirred at 80° C. for 22.5 h and is subsequently cooled slowly. Thedischarge is centrifuged and, after removal of the catalyst, worked upby distillation (yield: 85%). The catalyst can be employed anew afterwashing with water.

5) Synthesis of diethylaminobutynol Using the Catalyst from Example 3

56.1 g (0.55 mol) of propargyl alcohol (55% strength solution in water),30.3 g of paraformaldehyde (1 mol) and 5.1 g of the activated malachitecatalyst from Example 3 are introduced into a 250 ml stirred apparatus.After heating to 80° C., 73.1 g (1 mol) of diethylamine are addeddropwise with stirring over the course of 1 h. The reaction mixture isthen stirred at 80° C. for 22.5 h and is subsequently cooled slowly. Thedischarge is centrifuged and, after removal of the catalyst, worked upby distillation (yield: 92%). The catalyst can be employed anew afterwashing with water.

6) Synthesis of butynediol Using the Catalyst from Example 3

56.1 g (0.55 mol) of propargyl alcohol (55% strength solution in water),101 g (1 mol) of formaldehyde (30% strength solution in water) and 5.1 gof the activated malachite catalyst from Example 3 are introduced into a250 ml stirred apparatus. After the reaction mixture has been heated to90° C. it is stirred at 90° C. for 22.5 hours, and then slowly cooled.The discharge is centrifuged and, after removal of the catalyst,analyzed by gas chromatography (30 m DBl column, injector temperature260° C., detector temperature 280° C., Hewlett Packard HP 580 90Aapparatus, temperature program: initial temperature 80° C., heating rate10° C./min, final temperature 280° C.) (yield 80%).

We claim:
 1. A process for preparing a catalyst by activating acatalytic composition which comprises a) at least one metal of group IBor IIB or a compound thereof, b) where appropriate a carrier whichcomprises treating the composition with an alkyne of the general formulaI R¹—C≡C—R²  (I) in which R¹ is alkyl, cycloalkyl, aryl, hydroxyalkyl,haloalkyl, alkoxy or alkoxyalkyl, R² is a hydrogen atom, alkyl,cycloalkyl or aryl, and a carbonyl compound of the general formula II

in which R³ and R⁴ are, independently of one another, a hydrogen atom,alkyl, haloalkyl, cycloalkyl or aryl.
 2. A process as claimed in claim1, wherein copper or a copper compound, preferably selected from copperoxide and malachite, is employed as component a).
 3. A process asclaimed in claim 1, wherein the catalytic composition also containsbismuth or a bismuth compound which is preferably selected from Bi₂O₃,(BiO)₂CO₃, Bi(NO₃)₃ and BiO(NO₃).
 4. A process as claimed in claim 1,wherein a catalytic composition which comprises 10 to 20% by weightcopper(II) oxide, 1 to 5% by weight bismuth oxide and 75 to 89% byweight silica is employed.
 5. A process as claimed in claim 1, wherein apreviously used, deactivated catalyst is employed as catalyticcomposition.
 6. A process as claimed in claim 1, wherein an alkyne ofthe formula I in which R¹ is alkyl or hydroxyalkyl is employed.
 7. Aprocess as claimed in claim 1, wherein an alkyne of the formula I inwhich R² is a hydrogen atom or alkyl is employed.
 8. A process asclaimed in claim 1 wherein a carbonyl compound of the formula II inwhich R³ and R⁴ are, independently of one another, a hydrogen atom oralkyl, is employed.
 9. A catalyst obtainable by a process as claimed inclaim
 1. 10. A process for preparing alkynols of the general formula III

in which R⁵ is a hydrogen atom, alkyl, haloalkyl, cycloalkyl, aryl,alkoxy, alkoxyalkyl or a —C(R⁶R⁷)OH substituent, R⁶ and R⁷ are,independently of one another, a hydrogen atom, alkyl, haloalkyl,cycloalkyl or aryl, by reacting a mixture of an alkyne of the generalformula IV R⁵—C≡C—H  (IV) in which R⁵ has the meanings stated above, anda carbonyl compound of the general formula V

in which R⁶ and R⁷ have the meanings stated above, wherein the reactiontakes place in the presence of a catalyst as claimed in claim
 9. 11. Aprocess for preparing aminoalkynes of the general formula VI

in which R⁵, R⁶ and R⁷ have the meanings stated above, R⁸ and R⁹ are,independently of one another, a hydrogen atom, alkyl, haloalkyl,cycloalkyl, aryl or hydroxyalkyl, or R⁸ and R⁹ form, together with thenitrogen atom to which they are bonded, a 5- or 6-membered heterocyclicring; by reacting a mixture of an alkyne of the general formula IVR⁵—C≡C—H  (IV) in which R⁵ has the meanings stated above, a carbonylcompound of the general formula V

in which R⁶ and R⁷ have the meanings stated above, and an amine of thegeneral formula VII

in which R⁸ and R⁹ have the meanings stated above, wherein the reactiontakes place in the presence of a catalyst as claimed in claim
 9. 12. Aprocess as claimed in claim 1, wherein the catalytic composition istreated under atmospheric pressure.